Table 1.
Clinicopathological data of RA patients at biopsy.*
Figure 1.
Expression of gp38 in synovial tissues.
(A) IHC immunoperoxidase labelling of gp38 expression in normal, OA and RA tissues. RA CTRL: IgG1 isotype control. Lining and sublining areas, and a large lymphoid aggregate centered by a HEV (arrows) are shown. Bar: 50 µm. Original magnification 400x (B) Changes in gp38 expression after anti-TNF therapy. Representative imunoperoxidase labeling of gp38 of a single patient pre- and post-treatment. Bar: 100 µm. Original magnification 200x (C) Mean±SD gp38 immunostained fractional area in the different groups (OA vs RA Mann Whitney test *p<0.0001), and in basal (Pre) and post-anti-TNF-α therapy (Post) in 16 patients (RA Pre vs RA Post Wilcoxon matched-pairs signed rank test *p<0.0001).
Table 2.
Clinicopathological correlations of gp38 expression* in RA synovial tissue.
Figure 2.
gp38 expression of cultured synovial fibroblasts.
SF from RA, OA and normal synovial tissues, and normal skin dermal fibroblasts (DF) were cultured on glass coverslips and immunolabeled (red) for gp38 expression. TNF-α treated DF cultures are also shown (DAPI nuclear counterstaining). Flow cytometric detection of surface gp38 by in RA SF and DF untreated (basal) or treated with TNF-α for 24h. Data are representative of 6 SF and 3 DF lines (*p = 0.03 basal vs TNF-α treated). MFI: Mean fluorescence intensity.
Figure 3.
Detection of CLEC2 expression in synovial tissues.
IHC immunoperoxidase labelling of CLEC2 receptor and CD61 (platelets) in OA, RA and normal synovial tissues as indicated. Non immune serum control for anti-CLEC2 IHC is also shown (RA CTRL). Bar: 50 µm. Original magnification 400x.
Figure 4.
Expression of cytokines and chemokines in gp38 silenced RA SF platelet co-cultures.
(A) Magnitude of the up-regulation on IL-6, IL-8, CXCL2 and CXCL3 mRNA expression induced by platelets and expressed as the ratio (FC) between SF and platelet co-cultures compared to parallel SF only cultures in gp38 siRNA silenced SF and non-silenced controls (si-CTRL) as measured by qRT-PCR. (B) IL-6 protein levels in supernatants of platelet cocultured gp38 siRNA silenced SF compared to non-silenced controls as measured by ELISA. Mean±SD data are representative of 3 independent experiments (*p = 0.0002, **p = 0.01, ***p<0.0001).